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Updated: Aug 2, 2026

FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
[Prenatal cytogenetic diagnosis in older pregnant women]
I Kalina1, A Ondrusseková, S Lukacín
1Ustav lekárskej biológie LF UPJS, Kosice.
Abstract:
The paper deals with the genetic risk of advanced age of women assessed on the basis of prenatal cytogenetic analysis during the second trimester of gestation. The examined group comprised 614 pregnant women older than 35 years. The cells for chromosomal analysis were obtained by transabdominal amniocentesis during the 16th to 18th week of gestation. Cytogenetic examination revealed that the general risk of an aneuploid foetus in women of more advanced age is 2.12% and the most frequently encountered chromosomal aberration was trisomy 21 which was confirmed in 1.30 cytogenetically examined foetuses.
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